水稻脱落酸响应基因分析

脱落酸(ABA)参与调节植物的生长和发育,在植物抗击外界环境压力方面起到了重要的作用。为了筛选出水稻体内的脱落酸响应基因,试验设计了OsRD22,OsLTP4,OsLEA7的定量PCR引物,同时利用以终浓度为50μmol/L的外源脱落酸处理的水稻叶片为材料,分析3种基因对外源脱落酸的响应情况。结果表明,随着外源脱落酸处理时间的延长,OsLTP4,OsLEA7等2种基因的相对转录水平并没有随之增长;OsRD22基因的相对转录水平随着时间的增加,呈现出表达量逐渐升高的趋势。因此,基因OsRD22的表达水平可以作为测定水稻叶片内脱落酸相对含量的指标。

猪链球菌2型分离株精氨酸脱亚氨酸酶遗传变异分析

为了分析猪链球菌2型(SS2)发病原因、流行趋势,为预防和控制猪链球菌2型提供理论依据,根据GenBank发表的猪链球菌精氨酸脱亚氨酸酶(arginine dei minase,ADS)基因序列,设计并合成引物,采用RT-PCR技术,对阳性病料进行扩增,回收扩增产物并将其克隆入pMD18-T载体中,提取质粒测序。应用DNAStar软件分析核苷酸序列的同源性,并绘制系统进化树。结果显示,分离株HN1-HN8核苷酸的同源性为94.9%～100%,来自同一地区的分离株HN5和HN6同源性为100%,而河南分离株与GenBank发表的SX332同源性为95.9%～99.2%。因此,同一地域分离株间ADS基因序列同源性较高且亲缘关系较近,不同地域则较远。

含酸原油腐蚀与脱酸

本文介绍了环烷酸的腐蚀机理及影响因素，探讨了国内外脱酸工艺的进展。

猪链球菌精氨酸脱亚氨酸酶序列分析及其PCR检测

对9株猪链球菌2型重庆分离株的精氨酸脱亚氨酸酶基因进行克隆测序,结果表明该基因长度为1231bp,与Genbank发表的该基因序列相比,核苷酸同源性高于99%,推导的氨基酸同源性高于96%。根据精氨酸脱亚氨酸酶基因的测序结果建立扩增片段长度为237bp的PCR检测方法,35株猪链球菌致病株中,30株精氨酸脱亚氨酸酶基因的PCR检测阳性,有5株精氨酸脱亚氨酸酶基因的PCR检测阴性;14株正常猪扁桃体分离株中,11株为精氨酸脱亚氨酸酶基因的PCR检测阳性,3株为精氨酸脱亚氨酸酶基因的PCR检测阴性;猪链球菌1型、7型、9型、13型、1/2型各一株,均能扩增出精氨酸脱亚氨酸酶基因的片段。

ABA及其合成抑制剂钨酸钠处理对平榛胚珠发育的影响

研究了平榛(Corylus heterophylla Fisch)正常胚珠与败育胚珠在果实发育期间4种植物内源激素的变化动态,并使用ABA与其合成抑制剂钨酸钠对果序进行喷施处理,研究其对胚珠发育的影响。结果表明:(1)在正常充实胚珠中,IAA、GA3与ZR含量均大致呈单峰曲线,峰值分别出现在花后80、90和100d,同期相比,败育胚珠中IAA、GA3多数低于前者,而ZR含量多数高于前者;花后80～110d是胚珠快速生长期,在此期间,正常发育胚珠中ABA的含量显著高于败育胚珠;(2)与对照相比,50.0和20.0mg·L-1的ABA处理不同程度的提高了果实种仁质量、果壳质量及果实总质量等,而ABA合成抑制剂钨酸钠处理效果与ABA相反,表明ABA参与调控了榛子胚珠充实发育的进程。

In Vivo Tissue-dependent Abscisic Acid Specific-binding Proteins with High Affinity in Cytosol of Developing Apple Fruits

The in vivo highly tissue-dependent abscisic acid (ABA) specific-binding sites localized in cytosol were identified and characterized in the flesh of developing apple ( Malus pumila L. cv. Starkrimon) fruits. ABA binding activity was scarcely detectable in the microsomes and the cytosolic fraction isolated from the freshly harvested fruits via an in vitro ABA binding incubation of the subcellular fractions. If, however, instead that the subcellular fractions were in vitro incubated in H-3-ABA binding medium, the flesh tissue discs were directly in vivo incubated in H-3-ABA binding medium, a high ABA binding activity to the cytosolic fraction isolated from these tissue discs was detected. The in vivo ABA binding capacity of the cytosolic fraction was lost if the tissue discs had been pretreated with boiling water, indicating that the ABA binding needs a living state of tissue. The in vivo tissue-dependent binding sites were shown to possess protein nature with both active serine residua and thiol-group of cysteine residua in their functional binding center. The ABA binding of the in vivo tissue-dependent ABA binding sites to the cytosolic fraction was shown to be saturable, reversible, and of high affinity. The scatchard plotting gave evidence of two different classes of ABA binding proteins, one with a higher affinity ( Kd = 2.9 nmol/L) and the other with lower affinity ( Kd = 71.4 nmol/L). Phaseic acid, 2-trans-4-trans-ABA or cis-trans-(-)-ABA had substantially no affinity to the binding proteins, indicating their stereo-specificity to bind physiologically active ABA. The time course, pH- and temperature-dependence of the in vivo tissue-dependent binding proteins were determined. It is hypothesized that the detected ABA-binding proteins may be putative ABA-receptors that mediate ABA signals during fruit development.

Removal of S^(2-) ion from sodium aluminate solutions with sodium ferrite

The synthesis of sodium ferrite and its desulfurization performance in S2 -bearing sodium aluminate solutions were investigated. The thermodynamic analysis shows that the lowest temperature is about 810 K for synthesizing sodium ferrite by roasting the mixture of ferric oxide and sodium carbonate. The results indicate that the formation process of sodium ferrite can be completed at 1173 K for 60 min, meanwhile raising temperature and reducing NazCO3 particle size are beneficial to accelerating the formation of sodium ferrite. Sodium ferrite is an efficient desulfurizer to remove the S2- in aluminate solution, and the desulfurization rate can reach approximately 70% at 373 K for 60 min with the molar ratio of iron to sulfur of 1：1-1.5：1. Furthermore, the desulfurization is achieved by NaFeS2·2H2O precipitation through the reaction of Fe（OH）4 and S^2- in aluminate solution, and the desulfurization efficiency relies on the Fe（OH）4^- generated by dissolving sodium ferrite.

Determination of Isotherm for Acetate and Formate Adsorption at Pt（111） Electrode by Fast Scan Voltammetry

Fast scan voltammetry is an efficient tool to distinguish oxidative/reductive adsorp- tion/desorption from that for bulk reaction. In this work, we provide a methodology that the isotherm of oxidative/reductive adsorption desorption processes at electrode surface can be obtained using just one solution with relatively low reactant concentration, by taking the advantage of varying the potential scan rate （relative of the diffusion rate） to tune the adsorption rate and proper mathematic treatment. The methodology is demonstrated by taking acetate adsorption at Pt（lll） in acidic solution as an example. The possibility for extension of this method toward mechanistic studies of complicated electrocatalytic reactions is also given.

Involvement of cAMP in ABA Signal Transduction in Tobacco Suspension Cells

Abscisic acid (ABA) plays an important role in plant growth and developmental processes. Although some ABA signal molecules, such as cADPR, Ca2+, etc., have been reported, there. was no evidence proving the involvement of cAMP in A-B-A, signal transduction. In this present study, the constructed gene ( rd29A-GUS) was transformed into Nicotiana tabacum, and calli was induced from the transgenic plant. The suspension cells obtained from the callus grew well and uniformly. Treatment of the suspension cells with ABA led to an increase in GUS activity, indicating that these transgenic suspension cells are useful for the study of ABA signaling. Addition of nicotinamide (cADPR inhibitor) or U-73122 (phospholiphase C inhibitor) could only partially inhibit the increase of GUS activity elicited by ABA. The inhibitory effect of nicotinamide was enhanced by application of K252a (inhibitor of protein kinase). Treatment of the suspension cells with 8-Br-cAMP, a membrane-permeable analogue of cAMP, could partially replace the effect of ABA. Furthermore, intracellular addition of IBMX (phosphodiesterase inhibitor) mimicked die effect of exogenous cAMP on the deduction of expression of rd29A promoter. These results suggested that cAMP was an important messenger in ABA signal transduction in tobacco suspension cell.

Alkali-metal-modified ZSM-5 zeolites for improvement of catalytic dehydration of lactic acid to acrylic acid

Various ZSM-5 zeolites modified with alkali metals （Li, Na, K, Rb, and Cs） were prepared using ion exchange. The catalysts were used to enhance the catalytic dehydration of lactic acid （LA） to acrylic acid （AA）. The effects of cationic species on the structures and surface acid-base distributions of the ZSM-5 zeolites were investigated. The important factors that affect the catalytic performance were also identified. The modified ZSM-5 catalysts were characterized using X-ray diffraction, tempera- ture-programmed desorptions of NH3 and CO2, pyridine adsorption spectroscopy, and N2 adsorption to determine the crystal phase structures, surface acidities and basicities, nature of acid sites, specific surface areas, and pore volumes. The results show that the acid-base sites that are adjusted by alkali-metal species, particularly weak acid-base sites, are mainly responsible for the formation of AA. The KZSM-5 catalyst, in particular, significantly improved LA conversion and AA selectivity because of the synergistic effect of weak acid-base sites. The reaction was conducted at different reaction temperatures and liquid hourly space velocities （LHSVs） to understand the catalyst selectivity for AA and trends in byproduct formation. Approximately 98% LA conversion and 77% AA selectivity were achieved using the KZSM-5 catalyst under the optimum conditions （40 wt% LA aqueous solution, 365 ℃, and LHSV 2 h-1）.

Study on Preservative Formula and Shelf Life of Cantonese Style Moon Cakes

To ensure the safety of consumers, prolong the shelf life of moon cake and reduce the cost of manufacturing and marketing enterprises, the optimization of preservative formula and the shelf life of cantonese style moon cake were studied. Through single and compound formula preservative test, the results showed that potassium sorbate and sodium dehydroacetate could inhibit the microorganisms in the moon cake, but the inhibitory effect of sodium dehydroacetate was stronger than that of potassium sorbate; and the combination of potassium sorbate and sodium dehydroacetate had a synergistic effect, and the best formula is ＇potassium sorbate 0.44 g/kg mixed with sodium dehydroacetate 0.38 g/kg. A batch of moon cake was prepared with the best preservative formula, then the total number of colonies, molds and coliform group in the samples were detected by random sampling at irregular intervals. The total number of molds exceeded the limit on the 187^th d, and it indicated that the shelf life of the product was 187 d. Compared with the conventional 15-day shelf life, this research greatly prolongs the sheff life of cantonese style moon cake, and cut down the cost of moon cake enterprises. It is worthy of popularization and application.

Evaluation of Catalysts and Optimization of Reaction Conditions for the Dehydration of Methyl Lactate to Acrylates

The production of acrylates from biomass-originated lactic acid is of extraordinary importance, to overcome the increasing worldwide shortage of petroleum. In this study, the catalytic dehydration of methyl lactate over a calcium sulfate catalyst, with various promoters, has been carried out to identify potential catalyst/promoter combinations for acrylate production. The best catalyst for methyl acrylate formation in this study has been calcium sulfate, with cupric sulfate and phosphates as promoters. The optimal mass ratio of m（CaSOa） ： m（CuSOa） ： m（Na2HPO4） ： m（KH2PO4） is 150.0 ： 13.8 ： 2.5 ： 1.2. Effects of carrier gas, reaction temperature, feed concentration as well as contact time on the dehydration of methyl lactate have been investigated. With nitrogen as a carrier gas, a combined yield of acrylic acid and methyl acrylate is 63.9% from 60% （by mass） methyl lactate at 400℃ with 7.7 seconds contact time.

Production of γ-linolenic acid and stearidonic acid by Synechococcus sp.PCC7002 containing cyanobacterial fatty acid desaturase genes

Genetic modifi cation is useful for improving the nutritional qualities of cyanobacteria. To increase the total unsaturated fatty acid content, along with the ratio of ω-3/ω-6 fatty acids, genetic engineering can be used to modify fatty acid metabolism. S ynechococcus sp. PCC7002, a fast-growing cyanobacterium, does not contain a Δ6 desaturase gene and is therefore unable to synthesize γ-linolenic acid(GLA) and stearidonic acid(SDA), which are important in human health. In this work, we constructed recombinant vectors Syd6 D, Syd15 D and Syd6Dd15 D to express the Δ15 desaturase and Δ6 desaturase genes from Synechocystis PCC6803 in Synechococcus sp. PCC7002, with the aim of expressing polyunsaturated fatty acids. Overexpression of the Δ15 desaturase gene in S ynechococcus resulted in 5.4 times greater accumulation of α-linolenic acid compared with the wild-type while Δ6 desaturase gene expression produced both GLA and SDA. Co-expression of the two genes resulted in low-level accumulation of GLA but much larger amounts of SDA, accounting for as much to 11.64% of the total fatty acid content.

Analysis of LDH activities and its isoenzyme patterns in colorectal cancer tissues

AIM To investigate the relationship between lactate dehydrogenase (LDH) activity or LDH isoenzyme pattern and the pathogenesis of colorectal cancer.

Activity and Stability of Arginine Deiminase for Producing L-citrulline

A novel Enterococcus faecalis strain designated N J402 was found with high activity of arginine deiminase （ADI）. The optimum condition for catalytic activity was determined in terms of temperature （about 40℃）, thermostability （available 37℃） and pH （6-7）. The effects of substrate and product concentration were studied. The effects of various metal ions added in reaction mixtures on the biocatalyst were investigated and ADI of N J402 was found to exhibit Co^2＋ dependence, different from previous reports. Surfactant, cetyl trimethyl ammonium bromide, was one of the most important keys for producing L-citrulline. The enzyme in resting cells possessed the quality of high stability for reuse.

DIETARY PHOSPHORUS REQUIREMENT OF YOUNG ABALONE, HALIOTIS DISCUS HANNAI INO.

An experiment was performed to determine the dietary phosphorus requirement of the young abalone, Haliotis discus hannai. Five semi-purified diets were formulated to provide a series of graded levels of dietary total phosphorus (0.23%-1.98) from monobasic potassium phosphate (KH2PO4). The brown alga, Laminaria japonica, was used as a control diet. Similar size abalone were distributed in a single-pass, flow-through system using a completely randomized design with six treatments and three replicates each treatment. The abalone were hand-fed to satiation with appropriate diets in excess, once daily at 17:00. The feeding trial was run for 120-d. Survival rate and soft-body to shell ratio (SB/S) were constantly maintained regardless of dietary treatment. However, the weight gain rate (WGR), daily increment in shell length (DISL), muscle RNA to DNA ratio (RNA/DNA), carcass levels of lipid and protein, soft-body alkaline phosphatase (SBAKP), and phosphorus concentrations of whole body (WB) and soft body (SB) were significantly (ANOVA, P<0.05) affected by the dietary phosphorus level. The dietary phosphorus requirements of the abalone were evaluated from the WGR, DISL, and RNA/DNA ratio respectively, by using second-order polynomial regression analysis. Based on these criteria, about 1.0%-1.2% total dietary phosphorus, i.e. 0.9%-1.1% dietary available phosphorus is recommended for the maximum growth of the abalone.

Decreased mitochondrial deoxyribonucleic acid and increased oxidative damage in chronic hepatitis C

AIM： To determine whether alteration of the mito- chondria DNA （mtDNA） copy number and its oxidative damage index （mtDNA△CT） can be detected by analysis of peripheral blood cells in hepatitis C virus （HCV）- infected patients. METHODS： This study enrolled two groups of pa- tients aged 40-60 years： a control group and an HCV- infected group in Department of Gastroenterology and Hepatology in Changhua Christian Hospital. Patients with co-infection with hepatitis B virus or human im- munodeficiency virus, autoimmune disease, malignant neoplasia, pregnancy, thyroid disease, or alcohol con- sumption 〉 40 g/d were excluded. HCV-infected pa- tients who met the following criteria were included： （1） positive HCV antibodies for 〉 6 mo; （2） alanine aminotransferase （ALT） levels more than twice the upper lim- it of normal on at least two occasions during the past 6 mo; and （3） histological fibrosis stage higher than F1. The mtDNA copy number and oxidative damage index of HCV mtDNA （mtDNA△CT） were measured in periph- eral blood leukocytes. The association between mtDNA copy number and mtDNA△CT was further analyzed using clinical data. RESULTS： Forty-seven normal controls （male/female： 26/21, mean age 50.51 ± 6.15 years） and 132 HCV- infected patients （male/female： 76/61, mean age 51.65 ± 5.50 years） were included in the study. The geno- types of HCV-infected patients include type 1a （n = 3）, type 1b （n = 83）, type 2a （n = 32）, and type 2b （n = 14）. Liver fibrosis stages were distributed as follows： F1/F2/F3/F4 = 1/61/45/25 and activity scores were A0/ A1/A2/A3 = 7/45/55/25. There were no age or gender differences between the two groups. HCV-infected pa- tients had higher hepatitis activity （aspartate transami- nase levels 108.77 ± 60.73 vs 23.19 ± 5.47, P 〈 0.01; ALT levels 168.69 ± 93.12 vs 23.15 ± 9.45, P 〈 0.01） and lower platelet count （170.40±58.00 vs 251.24 ± 63.42, P 〈 0.01） than controls. The mtDNA copy num- ber was lower in HCV-infected patients than in controls （173.49 vs 247.93, P 〈 0.05）. The mtDNA△CT was higher in HCV-infected patients than in controls （2.92 vs 0.64, P 〈 0.05）. To clarify the clinical significance of these results in HCV-infected patients, their association with different clinical parameters among HCV-infected pa- tients was analyzed. A negative association was found between mtDNA copy number and elevated aspartate transaminase levels （r = -0.17, P 〈 0.05）. Changes in mtDNA copy number were not associated with HCV RNA levels, HCV genotypes, liver fibrosis severity, or inflammatory activity in the liver biopsy specimen. How- ever, a correlation was observed between mtDNA△CT and platelet count （r = -0.22, P 〈 0.01）, HCV RNA level （r = 0.36, P 〈 0.01）, and hepatitis activity （r = 0.20, P = 0.02）. However, no difference in the change in mtDNA△CT was observed between different fibrosis stages or HCV CONCLUSION： Oxidative stress and mtDNA dam- age are detectable in patient＇s peripheral leukocytes. Increased leukocyte mtDNA△CT correlates with higher HCV viremia, increased hepatitis activity, and lower platelet count.

Oxidative Desulfurization of Model Sulfur Compound by Potassium Ferrate in the Presence of Phosphomolybdic Acid Catalyst

In this work, the removal of thiophene from simulated oil has been studied by using the adsorption, extraction and oxidation/adsorption methods, respectively. In the adsorptive desulfurization process, different commercial adsorbents were used to eliminate thiophene at ambient pressure and mild temperature, and the results showed that carbon powder had the best adsorption ability. In the extractive desulfurization process, the best desulfurization result was obtained when DMF is used. In the oxidative/adsorptive desulfurization procedure using synthesized potassium ferrate as the oxidant and phosphomolybdic acid solution as the catalyst, thiophene was oxidized and removed from hydrocarbons in combination with active carbon adsorption, and the residual sulfur content of simulated oil could be reduced to 15.3mg/L from the original level of 200mg/L, with the desulfurization rate reaching 92.3%.

Electrolytic Regeneration of Decarbonising Potassium Carbonate Solution

In this work,the regeneration mechanism of potassium carbonate solution after absorption of CO2 using ion-exchange membrane electrolysis was presented.The solutions of potassium carbonate(K2CO3) and potassium bicarbonate(KHCO3) were used to simulate the solution after absorbing CO2.Experiments were carried out at various electrodes,temperatures and current densities.The results indicate that the membrane electrolysis can in-crease concentration ratio of K2CO3 and KHCO3,and achieve 100%conversion.In this process,not only CO2 is desorbed from carbonate solution,but also hydrogen,as a byproduct,is generated at the cathode,which is the main contributor to reduce energy consumption.Thus,the membrane electrolysis is valuable in the regeneration of the K2CO3 absorbent.

子囊霉素工程菌的构建及初步发酵工艺优化

基于子囊霉素的生物合成途径和机制,根据生物合成基因簇序列设计引物,应用PCR扩增游动放线菌(Antinoplanes sp.)N902-109赖氨酸合成途径关键基因——天冬氨酸激酶/天冬氨酸半醛脱氢酶/磷酸烯醇式丙酮酸羧化酶(lysC/asd/ppc)基因,整合至子囊霉素产生菌株吸水链霉菌(Streptomyces hygroscopicus)中,成功构建了过表达lysC/asd/ppc基因的重组工程菌,命名为AS-07。将AS-07工程菌进行摇瓶发酵研究,结果表明,与野生菌相比,子囊霉素的产量提高了25%。通过初步优化摇瓶发酵工艺,AS-07工程菌与野生菌相比,子囊霉素的产量提高了85%。